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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2015-2016 Free Electrons
4 * Copyright (C) 2015-2016 NextThing Co
5 *
6 * Maxime Ripard <maxime.ripard@free-electrons.com>
7 */
8
9#include <linux/gpio/consumer.h>
10#include <linux/module.h>
11#include <linux/of_device.h>
12#include <linux/of_graph.h>
13#include <linux/regulator/consumer.h>
14
15#include <drm/drm_atomic_helper.h>
16#include <drm/drm_bridge.h>
17#include <drm/drm_crtc.h>
18#include <drm/drm_print.h>
19#include <drm/drm_probe_helper.h>
20
21struct simple_bridge_info {
22 const struct drm_bridge_timings *timings;
23 unsigned int connector_type;
24};
25
26struct simple_bridge {
27 struct drm_bridge bridge;
28 struct drm_connector connector;
29
30 const struct simple_bridge_info *info;
31
32 struct drm_bridge *next_bridge;
33 struct regulator *vdd;
34 struct gpio_desc *enable;
35};
36
37static inline struct simple_bridge *
38drm_bridge_to_simple_bridge(struct drm_bridge *bridge)
39{
40 return container_of(bridge, struct simple_bridge, bridge);
41}
42
43static inline struct simple_bridge *
44drm_connector_to_simple_bridge(struct drm_connector *connector)
45{
46 return container_of(connector, struct simple_bridge, connector);
47}
48
49static int simple_bridge_get_modes(struct drm_connector *connector)
50{
51 struct simple_bridge *sbridge = drm_connector_to_simple_bridge(connector);
52 struct edid *edid;
53 int ret;
54
55 if (sbridge->next_bridge->ops & DRM_BRIDGE_OP_EDID) {
56 edid = drm_bridge_get_edid(sbridge->next_bridge, connector);
57 if (!edid)
58 DRM_INFO("EDID read failed. Fallback to standard modes\n");
59 } else {
60 edid = NULL;
61 }
62
63 if (!edid) {
64 /*
65 * In case we cannot retrieve the EDIDs (missing or broken DDC
66 * bus from the next bridge), fallback on the XGA standards and
67 * prefer a mode pretty much anyone can handle.
68 */
69 ret = drm_add_modes_noedid(connector, 1920, 1200);
70 drm_set_preferred_mode(connector, 1024, 768);
71 return ret;
72 }
73
74 drm_connector_update_edid_property(connector, edid);
75 ret = drm_add_edid_modes(connector, edid);
76 kfree(edid);
77
78 return ret;
79}
80
81static const struct drm_connector_helper_funcs simple_bridge_con_helper_funcs = {
82 .get_modes = simple_bridge_get_modes,
83};
84
85static enum drm_connector_status
86simple_bridge_connector_detect(struct drm_connector *connector, bool force)
87{
88 struct simple_bridge *sbridge = drm_connector_to_simple_bridge(connector);
89
90 return drm_bridge_detect(sbridge->next_bridge);
91}
92
93static const struct drm_connector_funcs simple_bridge_con_funcs = {
94 .detect = simple_bridge_connector_detect,
95 .fill_modes = drm_helper_probe_single_connector_modes,
96 .destroy = drm_connector_cleanup,
97 .reset = drm_atomic_helper_connector_reset,
98 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
99 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
100};
101
102static int simple_bridge_attach(struct drm_bridge *bridge,
103 enum drm_bridge_attach_flags flags)
104{
105 struct simple_bridge *sbridge = drm_bridge_to_simple_bridge(bridge);
106 int ret;
107
108 ret = drm_bridge_attach(bridge->encoder, sbridge->next_bridge, bridge,
109 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
110 if (ret < 0)
111 return ret;
112
113 if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)
114 return 0;
115
116 if (!bridge->encoder) {
117 DRM_ERROR("Missing encoder\n");
118 return -ENODEV;
119 }
120
121 drm_connector_helper_add(&sbridge->connector,
122 &simple_bridge_con_helper_funcs);
123 ret = drm_connector_init_with_ddc(bridge->dev, &sbridge->connector,
124 &simple_bridge_con_funcs,
125 sbridge->info->connector_type,
126 sbridge->next_bridge->ddc);
127 if (ret) {
128 DRM_ERROR("Failed to initialize connector\n");
129 return ret;
130 }
131
132 drm_connector_attach_encoder(&sbridge->connector, bridge->encoder);
133
134 return 0;
135}
136
137static void simple_bridge_enable(struct drm_bridge *bridge)
138{
139 struct simple_bridge *sbridge = drm_bridge_to_simple_bridge(bridge);
140 int ret;
141
142 if (sbridge->vdd) {
143 ret = regulator_enable(sbridge->vdd);
144 if (ret)
145 DRM_ERROR("Failed to enable vdd regulator: %d\n", ret);
146 }
147
148 gpiod_set_value_cansleep(sbridge->enable, 1);
149}
150
151static void simple_bridge_disable(struct drm_bridge *bridge)
152{
153 struct simple_bridge *sbridge = drm_bridge_to_simple_bridge(bridge);
154
155 gpiod_set_value_cansleep(sbridge->enable, 0);
156
157 if (sbridge->vdd)
158 regulator_disable(sbridge->vdd);
159}
160
161static const struct drm_bridge_funcs simple_bridge_bridge_funcs = {
162 .attach = simple_bridge_attach,
163 .enable = simple_bridge_enable,
164 .disable = simple_bridge_disable,
165};
166
167static int simple_bridge_probe(struct platform_device *pdev)
168{
169 struct simple_bridge *sbridge;
170 struct device_node *remote;
171
172 sbridge = devm_kzalloc(&pdev->dev, sizeof(*sbridge), GFP_KERNEL);
173 if (!sbridge)
174 return -ENOMEM;
175 platform_set_drvdata(pdev, sbridge);
176
177 sbridge->info = of_device_get_match_data(&pdev->dev);
178
179 /* Get the next bridge in the pipeline. */
180 remote = of_graph_get_remote_node(pdev->dev.of_node, 1, -1);
181 if (!remote)
182 return -EINVAL;
183
184 sbridge->next_bridge = of_drm_find_bridge(remote);
185 of_node_put(remote);
186
187 if (!sbridge->next_bridge) {
188 dev_dbg(&pdev->dev, "Next bridge not found, deferring probe\n");
189 return -EPROBE_DEFER;
190 }
191
192 /* Get the regulator and GPIO resources. */
193 sbridge->vdd = devm_regulator_get_optional(&pdev->dev, "vdd");
194 if (IS_ERR(sbridge->vdd)) {
195 int ret = PTR_ERR(sbridge->vdd);
196 if (ret == -EPROBE_DEFER)
197 return -EPROBE_DEFER;
198 sbridge->vdd = NULL;
199 dev_dbg(&pdev->dev, "No vdd regulator found: %d\n", ret);
200 }
201
202 sbridge->enable = devm_gpiod_get_optional(&pdev->dev, "enable",
203 GPIOD_OUT_LOW);
204 if (IS_ERR(sbridge->enable)) {
205 if (PTR_ERR(sbridge->enable) != -EPROBE_DEFER)
206 dev_err(&pdev->dev, "Unable to retrieve enable GPIO\n");
207 return PTR_ERR(sbridge->enable);
208 }
209
210 /* Register the bridge. */
211 sbridge->bridge.funcs = &simple_bridge_bridge_funcs;
212 sbridge->bridge.of_node = pdev->dev.of_node;
213 sbridge->bridge.timings = sbridge->info->timings;
214
215 drm_bridge_add(&sbridge->bridge);
216
217 return 0;
218}
219
220static int simple_bridge_remove(struct platform_device *pdev)
221{
222 struct simple_bridge *sbridge = platform_get_drvdata(pdev);
223
224 drm_bridge_remove(&sbridge->bridge);
225
226 return 0;
227}
228
229/*
230 * We assume the ADV7123 DAC is the "default" for historical reasons
231 * Information taken from the ADV7123 datasheet, revision D.
232 * NOTE: the ADV7123EP seems to have other timings and need a new timings
233 * set if used.
234 */
235static const struct drm_bridge_timings default_bridge_timings = {
236 /* Timing specifications, datasheet page 7 */
237 .input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE,
238 .setup_time_ps = 500,
239 .hold_time_ps = 1500,
240};
241
242/*
243 * Information taken from the THS8134, THS8134A, THS8134B datasheet named
244 * "SLVS205D", dated May 1990, revised March 2000.
245 */
246static const struct drm_bridge_timings ti_ths8134_bridge_timings = {
247 /* From timing diagram, datasheet page 9 */
248 .input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE,
249 /* From datasheet, page 12 */
250 .setup_time_ps = 3000,
251 /* I guess this means latched input */
252 .hold_time_ps = 0,
253};
254
255/*
256 * Information taken from the THS8135 datasheet named "SLAS343B", dated
257 * May 2001, revised April 2013.
258 */
259static const struct drm_bridge_timings ti_ths8135_bridge_timings = {
260 /* From timing diagram, datasheet page 14 */
261 .input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE,
262 /* From datasheet, page 16 */
263 .setup_time_ps = 2000,
264 .hold_time_ps = 500,
265};
266
267static const struct of_device_id simple_bridge_match[] = {
268 {
269 .compatible = "dumb-vga-dac",
270 .data = &(const struct simple_bridge_info) {
271 .connector_type = DRM_MODE_CONNECTOR_VGA,
272 },
273 }, {
274 .compatible = "adi,adv7123",
275 .data = &(const struct simple_bridge_info) {
276 .timings = &default_bridge_timings,
277 .connector_type = DRM_MODE_CONNECTOR_VGA,
278 },
279 }, {
280 .compatible = "ti,opa362",
281 .data = &(const struct simple_bridge_info) {
282 .connector_type = DRM_MODE_CONNECTOR_Composite,
283 },
284 }, {
285 .compatible = "ti,ths8135",
286 .data = &(const struct simple_bridge_info) {
287 .timings = &ti_ths8135_bridge_timings,
288 .connector_type = DRM_MODE_CONNECTOR_VGA,
289 },
290 }, {
291 .compatible = "ti,ths8134",
292 .data = &(const struct simple_bridge_info) {
293 .timings = &ti_ths8134_bridge_timings,
294 .connector_type = DRM_MODE_CONNECTOR_VGA,
295 },
296 },
297 {},
298};
299MODULE_DEVICE_TABLE(of, simple_bridge_match);
300
301static struct platform_driver simple_bridge_driver = {
302 .probe = simple_bridge_probe,
303 .remove = simple_bridge_remove,
304 .driver = {
305 .name = "simple-bridge",
306 .of_match_table = simple_bridge_match,
307 },
308};
309module_platform_driver(simple_bridge_driver);
310
311MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
312MODULE_DESCRIPTION("Simple DRM bridge driver");
313MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2015-2016 Free Electrons
4 * Copyright (C) 2015-2016 NextThing Co
5 *
6 * Maxime Ripard <maxime.ripard@free-electrons.com>
7 */
8
9#include <linux/gpio/consumer.h>
10#include <linux/module.h>
11#include <linux/of.h>
12#include <linux/of_graph.h>
13#include <linux/platform_device.h>
14#include <linux/regulator/consumer.h>
15
16#include <drm/drm_atomic_helper.h>
17#include <drm/drm_bridge.h>
18#include <drm/drm_crtc.h>
19#include <drm/drm_edid.h>
20#include <drm/drm_print.h>
21#include <drm/drm_probe_helper.h>
22
23struct simple_bridge_info {
24 const struct drm_bridge_timings *timings;
25 unsigned int connector_type;
26};
27
28struct simple_bridge {
29 struct drm_bridge bridge;
30 struct drm_connector connector;
31
32 const struct simple_bridge_info *info;
33
34 struct drm_bridge *next_bridge;
35 struct regulator *vdd;
36 struct gpio_desc *enable;
37};
38
39static inline struct simple_bridge *
40drm_bridge_to_simple_bridge(struct drm_bridge *bridge)
41{
42 return container_of(bridge, struct simple_bridge, bridge);
43}
44
45static inline struct simple_bridge *
46drm_connector_to_simple_bridge(struct drm_connector *connector)
47{
48 return container_of(connector, struct simple_bridge, connector);
49}
50
51static int simple_bridge_get_modes(struct drm_connector *connector)
52{
53 struct simple_bridge *sbridge = drm_connector_to_simple_bridge(connector);
54 const struct drm_edid *drm_edid;
55 int ret;
56
57 if (sbridge->next_bridge->ops & DRM_BRIDGE_OP_EDID) {
58 drm_edid = drm_bridge_edid_read(sbridge->next_bridge, connector);
59 if (!drm_edid)
60 DRM_INFO("EDID read failed. Fallback to standard modes\n");
61 } else {
62 drm_edid = NULL;
63 }
64
65 drm_edid_connector_update(connector, drm_edid);
66
67 if (!drm_edid) {
68 /*
69 * In case we cannot retrieve the EDIDs (missing or broken DDC
70 * bus from the next bridge), fallback on the XGA standards and
71 * prefer a mode pretty much anyone can handle.
72 */
73 ret = drm_add_modes_noedid(connector, 1920, 1200);
74 drm_set_preferred_mode(connector, 1024, 768);
75 return ret;
76 }
77
78 ret = drm_edid_connector_add_modes(connector);
79 drm_edid_free(drm_edid);
80
81 return ret;
82}
83
84static const struct drm_connector_helper_funcs simple_bridge_con_helper_funcs = {
85 .get_modes = simple_bridge_get_modes,
86};
87
88static enum drm_connector_status
89simple_bridge_connector_detect(struct drm_connector *connector, bool force)
90{
91 struct simple_bridge *sbridge = drm_connector_to_simple_bridge(connector);
92
93 return drm_bridge_detect(sbridge->next_bridge);
94}
95
96static const struct drm_connector_funcs simple_bridge_con_funcs = {
97 .detect = simple_bridge_connector_detect,
98 .fill_modes = drm_helper_probe_single_connector_modes,
99 .destroy = drm_connector_cleanup,
100 .reset = drm_atomic_helper_connector_reset,
101 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
102 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
103};
104
105static int simple_bridge_attach(struct drm_bridge *bridge,
106 enum drm_bridge_attach_flags flags)
107{
108 struct simple_bridge *sbridge = drm_bridge_to_simple_bridge(bridge);
109 int ret;
110
111 ret = drm_bridge_attach(bridge->encoder, sbridge->next_bridge, bridge,
112 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
113 if (ret < 0)
114 return ret;
115
116 if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)
117 return 0;
118
119 drm_connector_helper_add(&sbridge->connector,
120 &simple_bridge_con_helper_funcs);
121 ret = drm_connector_init_with_ddc(bridge->dev, &sbridge->connector,
122 &simple_bridge_con_funcs,
123 sbridge->info->connector_type,
124 sbridge->next_bridge->ddc);
125 if (ret) {
126 DRM_ERROR("Failed to initialize connector\n");
127 return ret;
128 }
129
130 drm_connector_attach_encoder(&sbridge->connector, bridge->encoder);
131
132 return 0;
133}
134
135static void simple_bridge_enable(struct drm_bridge *bridge)
136{
137 struct simple_bridge *sbridge = drm_bridge_to_simple_bridge(bridge);
138 int ret;
139
140 if (sbridge->vdd) {
141 ret = regulator_enable(sbridge->vdd);
142 if (ret)
143 DRM_ERROR("Failed to enable vdd regulator: %d\n", ret);
144 }
145
146 gpiod_set_value_cansleep(sbridge->enable, 1);
147}
148
149static void simple_bridge_disable(struct drm_bridge *bridge)
150{
151 struct simple_bridge *sbridge = drm_bridge_to_simple_bridge(bridge);
152
153 gpiod_set_value_cansleep(sbridge->enable, 0);
154
155 if (sbridge->vdd)
156 regulator_disable(sbridge->vdd);
157}
158
159static const struct drm_bridge_funcs simple_bridge_bridge_funcs = {
160 .attach = simple_bridge_attach,
161 .enable = simple_bridge_enable,
162 .disable = simple_bridge_disable,
163};
164
165static int simple_bridge_probe(struct platform_device *pdev)
166{
167 struct simple_bridge *sbridge;
168 struct device_node *remote;
169
170 sbridge = devm_kzalloc(&pdev->dev, sizeof(*sbridge), GFP_KERNEL);
171 if (!sbridge)
172 return -ENOMEM;
173
174 sbridge->info = of_device_get_match_data(&pdev->dev);
175
176 /* Get the next bridge in the pipeline. */
177 remote = of_graph_get_remote_node(pdev->dev.of_node, 1, -1);
178 if (!remote)
179 return -EINVAL;
180
181 sbridge->next_bridge = of_drm_find_bridge(remote);
182 of_node_put(remote);
183
184 if (!sbridge->next_bridge) {
185 dev_dbg(&pdev->dev, "Next bridge not found, deferring probe\n");
186 return -EPROBE_DEFER;
187 }
188
189 /* Get the regulator and GPIO resources. */
190 sbridge->vdd = devm_regulator_get_optional(&pdev->dev, "vdd");
191 if (IS_ERR(sbridge->vdd)) {
192 int ret = PTR_ERR(sbridge->vdd);
193 if (ret == -EPROBE_DEFER)
194 return -EPROBE_DEFER;
195 sbridge->vdd = NULL;
196 dev_dbg(&pdev->dev, "No vdd regulator found: %d\n", ret);
197 }
198
199 sbridge->enable = devm_gpiod_get_optional(&pdev->dev, "enable",
200 GPIOD_OUT_LOW);
201 if (IS_ERR(sbridge->enable))
202 return dev_err_probe(&pdev->dev, PTR_ERR(sbridge->enable),
203 "Unable to retrieve enable GPIO\n");
204
205 /* Register the bridge. */
206 sbridge->bridge.funcs = &simple_bridge_bridge_funcs;
207 sbridge->bridge.of_node = pdev->dev.of_node;
208 sbridge->bridge.timings = sbridge->info->timings;
209
210 return devm_drm_bridge_add(&pdev->dev, &sbridge->bridge);
211}
212
213/*
214 * We assume the ADV7123 DAC is the "default" for historical reasons
215 * Information taken from the ADV7123 datasheet, revision D.
216 * NOTE: the ADV7123EP seems to have other timings and need a new timings
217 * set if used.
218 */
219static const struct drm_bridge_timings default_bridge_timings = {
220 /* Timing specifications, datasheet page 7 */
221 .input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE,
222 .setup_time_ps = 500,
223 .hold_time_ps = 1500,
224};
225
226/*
227 * Information taken from the THS8134, THS8134A, THS8134B datasheet named
228 * "SLVS205D", dated May 1990, revised March 2000.
229 */
230static const struct drm_bridge_timings ti_ths8134_bridge_timings = {
231 /* From timing diagram, datasheet page 9 */
232 .input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE,
233 /* From datasheet, page 12 */
234 .setup_time_ps = 3000,
235 /* I guess this means latched input */
236 .hold_time_ps = 0,
237};
238
239/*
240 * Information taken from the THS8135 datasheet named "SLAS343B", dated
241 * May 2001, revised April 2013.
242 */
243static const struct drm_bridge_timings ti_ths8135_bridge_timings = {
244 /* From timing diagram, datasheet page 14 */
245 .input_bus_flags = DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE,
246 /* From datasheet, page 16 */
247 .setup_time_ps = 2000,
248 .hold_time_ps = 500,
249};
250
251static const struct of_device_id simple_bridge_match[] = {
252 {
253 .compatible = "dumb-vga-dac",
254 .data = &(const struct simple_bridge_info) {
255 .connector_type = DRM_MODE_CONNECTOR_VGA,
256 },
257 }, {
258 .compatible = "adi,adv7123",
259 .data = &(const struct simple_bridge_info) {
260 .timings = &default_bridge_timings,
261 .connector_type = DRM_MODE_CONNECTOR_VGA,
262 },
263 }, {
264 .compatible = "ti,opa362",
265 .data = &(const struct simple_bridge_info) {
266 .connector_type = DRM_MODE_CONNECTOR_Composite,
267 },
268 }, {
269 .compatible = "ti,ths8135",
270 .data = &(const struct simple_bridge_info) {
271 .timings = &ti_ths8135_bridge_timings,
272 .connector_type = DRM_MODE_CONNECTOR_VGA,
273 },
274 }, {
275 .compatible = "ti,ths8134",
276 .data = &(const struct simple_bridge_info) {
277 .timings = &ti_ths8134_bridge_timings,
278 .connector_type = DRM_MODE_CONNECTOR_VGA,
279 },
280 },
281 {},
282};
283MODULE_DEVICE_TABLE(of, simple_bridge_match);
284
285static struct platform_driver simple_bridge_driver = {
286 .probe = simple_bridge_probe,
287 .driver = {
288 .name = "simple-bridge",
289 .of_match_table = simple_bridge_match,
290 },
291};
292module_platform_driver(simple_bridge_driver);
293
294MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
295MODULE_DESCRIPTION("Simple DRM bridge driver");
296MODULE_LICENSE("GPL");